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III.G.1.a.

Comparison of levels of theory for B-S


Click on an entry for a histogram of the values.
The subscript refers to how many bonds of that type have been calculated.
average calculated bond lengths (Å)
Methods with predefined basis sets
semi-empirical AM1 1.4679
2
PM6 1.5993
4
composite G2 1.6160
4
G3 1.6160
4
G3B3 1.6351
4
G4 1.6269
4
CBS-Q 1.6193
4

average calculated bond lengths (Å)
Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z
hartree fock HF 1.5712
3
1.6436
4
1.6176
4
1.6568
4
1.6160
8
1.6161
4
1.6124
4
1.6128
4
1.6127
4
1.6129
4
1.5945
2
1.6105
4
1.6214
4
1.6093
4
1.6062
4
1.6212
4
1.6088
4
1.6060
4
1.5951
2
ROHF   1.6288
1
1.6053
1
  1.6022
1
1.6022
1
1.6024
1
1.6002
1
        1.6092
1
1.5986
1
         
density functional LSDA 1.5957
4
1.6414
4
1.6325
4
1.6668
4
1.6334
4
1.6334
4
1.6271
4
1.6238
4
1.6238
4
1.6266
4
    1.6365
4
1.6188
4
1.6292
2
1.6322
4
1.6301
2
1.6272
2
 
SVWN   1.6523
4
    1.6334
4
  1.6271
4
                       
BLYP 1.6215
3
1.6707
4
1.6492
4
1.6857
4
1.6505
4
1.6505
4
1.6443
4
1.6427
4
1.6426
4
1.6435
4
    1.6528
4
1.6359
4
  1.6328
2
     
B1B95 1.5895
4
1.6392
4
1.6297
4
1.6644
4
1.6329
4
1.6296
4
1.6240
4
1.6237
4
1.6237
4
1.6248
4
    1.6333
4
1.6182
4
1.6301
2
1.6298
4
1.6313
2
1.6286
2
 
B3LYP 1.5947
4
1.5422
4
1.6344
4
1.6710
4
1.6391
4
1.6350
4
1.6297
4
1.6281
4
1.6456
2
1.6287
4
1.6046
2
1.6249
4
1.6382
4
1.6223
4
1.6189
4
1.6351
4
1.6210
4
1.6182
4
1.6045
2
B3LYPultrafine         1.6391
4
                      1.6202
4
   
B3PW91 1.6130
2
1.6554
4
1.6333
4
1.6681
4
1.6325
4
1.6325
4
1.6273
4
1.6260
4
1.6433
2
1.6271
4
    1.6362
4
1.6213
4
  1.6188
2
     
mPW1PW91 1.5872
3
1.6527
4
1.6491
2
1.6652
4
1.6294
4
1.6293
4
1.6242
4
1.6234
4
1.6233
4
1.6245
4
    1.6332
4
1.6189
4
  1.6165
2
     
M06-2X         1.6248
4
                           
PBEPBE 1.6274
2
1.6675
4
1.6672
2
1.7048
2
1.6459
4
1.6459
4
1.6396
4
1.6390
4
1.6389
4
1.6402
4
1.6146
2
  1.6486
4
1.6336
4
1.6456
2
  1.6171
2
1.6436
2
1.6203
1
PBEPBEultrafine         1.6247
2
                           
PBE1PBE         1.6299
4
                           
HSEh1PBE         1.6305
4
                           
TPSSh         1.6340
4
  1.6297
4
            1.6246
4
         
Moller Plesset perturbation MP2 1.6206
2
1.6713
4
1.6404
4
1.6840
4
1.6271
5
1.6326
4
1.6273
4
1.6303
4
1.6301
4
1.6337
4
  1.6280
4
1.6475
4
1.6254
5
1.6074
1
1.6488
4
1.6295
4
1.6079
1
1.6074
2
MP2=FULL 1.6204
2
1.6713
4
1.6636
2
1.7100
2
1.6248
5
1.6302
4
1.6250
4
1.6293
4
1.6505
2
1.6502
2
    1.6460
4
1.6294
3
1.6028
1
1.6278
2
    1.6014
2
MP3         1.6225
4
  1.6220
4
                       
MP3=FULL         1.6200
4
  1.6158
4
                       
MP4   1.7346
2
    1.6499
4
    1.6197
2
1.6774
2
        1.6448
4
         
B2PLYP         1.6361
4
                1.6254
4
         
Configuration interaction CID   1.6834
2
1.6482
2
1.6989
2
1.6220
4
    1.6195
4
                     
CISD   1.6916
2
1.6532
2
1.7075
2
1.6265
4
    1.6424
2
                     
Quadratic configuration interaction QCISD   1.6797
4
1.6656
2
1.7240
2
1.6369
4
1.6584
2
1.6321
4
1.6350
4
1.6350
4
1.6567
2
    1.6518
4
1.6385
3
        1.6157
1
QCISD(T)         1.6426
4
    1.6205
2
        1.6800
2
1.6576
2
  1.6786
2
1.6562
2
   
Coupled Cluster CCD   1.6897
2
1.6548
2
1.7052
2
1.6260
4
1.6473
2
1.6373
2
1.6239
4
1.6439
2
1.6484
2
    1.6409
4
1.6405
2
  1.6606
2
1.6393
2
   
CCSD         1.6310
4
    1.6100
2
                     
CCSD(T)   1.6599
1
    1.6175
2
1.6177
2
1.6241
1
1.6175
2
1.6240
1
  1.6196
1
  1.6766
2
1.6443
3
  1.6755
2
1.6535
2
  1.6206
1
CCSD(T)=FULL         1.6592
2
                           

average calculated bond lengths (Å)
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 1.6731
4
1.6342
4
1.6682
4
1.6203
4
1.6549
4
1.6511
4
density functional B1B95 1.6591
1
1.6333
1
       
B3LYP 1.6961
4
1.6584
4
1.6902
4
1.6454
4
1.6754
4
1.6678
4
Moller Plesset perturbation MP2 1.7089
4
1.6580
4
1.6954
4
1.6410
4
1.6839
4
1.6802
4
For descriptions of the methods (AM1, HF, MP2, ...) and basis sets (3-21G, 3-21G*, 6-31G, ...) see the glossary in section I.C. Predefined means the basis set used is determined by the method.